At 06:02 -0800 1/22/13, Haemogoblin wrote: >I`m not a trained electrician or electronics engineer and I've now reached the >limits of my knowledge for fault testing this machine. So was wondering if >there's anyone on here, that might be able to advise me.
You sound more like an engineer than you think. Biongs, hissing as the high voltage drops, brightness turned up. I'd bet on, sorry, a blown filament in the picture tube. There has to be a source of electrons to bang into the screen and they come from a red-hot piece of tungsten wire coated with an emitter, I think, copper oxide.. Looking in the back of the tube, toward the connector, you should see a glow, A mirror on a stick will help.. Be careful for the 8 or so kilovolt line heading for the side of the tube. It's not the 25 kV in a modern color CRT but it's not something you want to learn about. The last time I found your symptoms the real problem was a crack in the picture tube where one of the connector pins goes thru the glass. It allowed air into the tube and the filament burned out. All of those monochrome tubes are the same for any version of a classic mac. -- --> From the U S of A, the only socialist country that refuses to admit it. <-- -- -- ----- You received this message because you are a member of the Vintage Macs group. The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to [email protected] To leave this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/vintage-macs Support for older Macs: http://lowendmac.com/services/
